Chemical paint removal processes commonly involve the application of organic, acid or basic formulations to the painted surface. In many cases, these formulations remain in contact with the painted surface for 48 hours or longer, providing sufficient time for porous surfaces such as wood, cement, brick, plaster, and the like to absorb the organic, acid or basic compounds present in the formulations, and thus to become contaminated with these compounds. This contamination may pose a health threat to those in the proximate surroundings of the treated surfaces, and often causes premature failure of coatings applied over the treated surfaces.
In order to reduce the future release of the organic, acid or basic compounds from contaminated surfaces, it is common practice to treat the surfaces with a post-paint removal wash designed to extract or neutralize the contaminant. For example, surfaces that were stripped with organic-based paint removers and that are thus contaminated with organic compounds are rinsed with an organic solvent; surfaces that were stripped with acidic paint removers and that are thus contaminated with acidic compounds are rinsed with a basic or caustic solution, and surfaces that were stripped with basic or caustic paint removers and that are thus contaminated with basic compounds are rinsed with an acidic solution.
There are several problems associated with this type of after-treatment, however. First, these treatments must be performed with careful understanding and monitoring of neutralization stoichiometry because over-treatment can result in the creation of a new hazard. For example, if a surface contaminated with a basic compound is after-treated with an excess of an acidic solvent, the resulting surface will be contaminated with an acidic compound. Additionally, washing the surfaces with these after-treatment solutions generates liquid hazardous waste that is difficult to collect and expensive to dispose of. For example, when washing a wall with an after-treatment solution, the solution will run onto the floors and may be absorbed into them, creating yet another contaminated surface. Thus, there is a need for a post-paint removal treatment process that can clean the surface, such as by neutralizing and/or removing the surface contaminant, without creating a new source of contaminant, and without creating liquid waste.